Gånger lika med produkt – det är frågan : En studie om lärares användande av det informella vardagsspråket och det formella matematikspråket

Sammanfattning: This study was based on our common interest in teachers’ use of language in algebra teaching. The purpose of the study is to investigate the teachers’ use of concepts in algebra teaching and to gain in-depth knowledge of how the teachers use formal mathematical language and informal everyday language. To produce results for the study, five teachers were studied in two separate math lessons, which was followed up with an interview to answer the following research questions: (1) How do the teachers use formal and informal concepts in the teaching of algebra? (2) What impact do the teachers think their language use has on the student's learning and own language use? (3) What conscious language choices do teachers make to support students' conceptual learning and to connect informal and formal language use?  The first research question, which was answered with the help of the study's observations and interviews, showed that the participating teachers use both informal and formal concepts in algebra teaching, in a varied and coexisting way. Both the language of mathematics and everyday language were considered necessary to combine in order to make mathematics teaching understandable for the students.  The second and third research questions, which were answered using the study's interviews, showed that most of the participating teachers believed that their language use has a high impact on students. One participating teacher mentioned that many students speak as the teacher does and therefore, the teacher's language becomes crucial for the student's language development. To support the students, most of the participating teachers used to confirm and repeat the informal concept that emerged and linked to the formal concept.